I'll try to simplify. Take fox/waltz and tango (BR) for example. Everyone talks about the walks being different between f/w and tango, btu never much about how/why. One would roll the feet from the floor in f/w which partly creates the softness/rolling actions of the dances. Yet, in tango, one places the foot/weight, thereby using the floor (placing the weight/moving over the foot) quite differently. Better? And, that's really good enough for most of the time.